In Response To 'Re: Mathematica 9 - SNA'---------That you get an ExportString warning when you Copy is strange.

First thing to try: reset preference and initialization files to default contents by holding down the SHIFT and OPTION keys as Mathematica starts. That will also clear the list of recently used notebook files. (If you think the SHIFT and OPTION method is not working, delete the folder
Library/Mathematica/FrontEnd
under your Home Directory (not the hard drive ikon).

If that does not fix it, any chance you could sent a notebook file (.nb) with a code example of what you are trying to do? Another notebook with the output from running SystemInformation[] would be helpful.
Email them to student-support@wolfram.com.